package types

import (
	"context"
	"time"

	abci "github.com/cometbft/cometbft/abci/types"
	cmtproto "github.com/cometbft/cometbft/proto/tendermint/types"

	"cosmossdk.io/core/comet"
	"cosmossdk.io/core/header"
	"cosmossdk.io/log"
	"cosmossdk.io/store/gaskv"
	storetypes "cosmossdk.io/store/types"
)

// ExecMode defines the execution mode which can be set on a Context.
type ExecMode uint8

// All possible execution modes.
const (
	ExecModeCheck ExecMode = iota
	ExecModeReCheck
	ExecModeSimulate
	ExecModePrepareProposal
	ExecModeProcessProposal
	ExecModeVoteExtension
	ExecModeVerifyVoteExtension
	ExecModeFinalize
)

/*
Context is an immutable object contains all information needed to
process a request.

It contains a context.Context object inside if you want to use that,
but please do not over-use it. We try to keep all data structured
and standard additions here would be better just to add to the Context struct
*/
type Context struct {
	baseCtx context.Context
	ms      storetypes.MultiStore
	// Deprecated: Use HeaderService for height, time, and chainID and CometService for the rest
	header cmtproto.Header
	// Deprecated: Use HeaderService for hash
	headerHash []byte
	// Deprecated: Use HeaderService for chainID and CometService for the rest
	chainID              string
	txBytes              []byte
	logger               log.Logger
	voteInfo             []abci.VoteInfo
	gasMeter             storetypes.GasMeter
	blockGasMeter        storetypes.GasMeter
	checkTx              bool
	recheckTx            bool // if recheckTx == true, then checkTx must also be true
	sigverifyTx          bool // when run simulation, because the private key corresponding to the account in the genesis.json randomly generated, we must skip the sigverify.
	execMode             ExecMode
	minGasPrice          DecCoins
	consParams           cmtproto.ConsensusParams
	eventManager         EventManagerI
	priority             int64 // The tx priority, only relevant in CheckTx
	kvGasConfig          storetypes.GasConfig
	transientKVGasConfig storetypes.GasConfig
	streamingManager     storetypes.StreamingManager
	cometInfo            comet.BlockInfo
	headerInfo           header.Info

	// For block-stm
	// // the index of the current tx in the block, -1 means not in finalize block context
	txIndex int
	// the index of the current msg in the tx, -1 means not in finalize block context
	msgIndex int
	// the total number of transactions in current block
	txCount int
	// sum the gas used by all the transactions in the current block, only accessible by end blocker
	blockGasUsed     uint64
	incarnationCache map[string]any // incarnationCache is shared between multiple incarnations of the same transaction, it must only cache stateless computation results that only depends on tx body and block level information that don't change during block execution, like the result of tx signature verification.
	// sum the gas wanted by all the transactions in the current block, only accessible by end blocker
	blockGasWanted uint64
}

// Proposed rename, not done to avoid API breakage

type Request = Context

// Read-only accessors

func (c Context) Context() context.Context                      { return c.baseCtx }
func (c Context) MultiStore() storetypes.MultiStore             { return c.ms }
func (c Context) BlockHeight() int64                            { return c.header.Height }
func (c Context) BlockTime() time.Time                          { return c.header.Time }
func (c Context) ChainID() string                               { return c.chainID }
func (c Context) TxBytes() []byte                               { return c.txBytes }
func (c Context) Logger() log.Logger                            { return c.logger }
func (c Context) VoteInfos() []abci.VoteInfo                    { return c.voteInfo }
func (c Context) GasMeter() storetypes.GasMeter                 { return c.gasMeter }
func (c Context) BlockGasMeter() storetypes.GasMeter            { return c.blockGasMeter }
func (c Context) IsCheckTx() bool                               { return c.checkTx }
func (c Context) IsReCheckTx() bool                             { return c.recheckTx }
func (c Context) IsSigverifyTx() bool                           { return c.sigverifyTx }
func (c Context) ExecMode() ExecMode                            { return c.execMode }
func (c Context) MinGasPrices() DecCoins                        { return c.minGasPrice }
func (c Context) EventManager() EventManagerI                   { return c.eventManager }
func (c Context) Priority() int64                               { return c.priority }
func (c Context) KVGasConfig() storetypes.GasConfig             { return c.kvGasConfig }
func (c Context) TransientKVGasConfig() storetypes.GasConfig    { return c.transientKVGasConfig }
func (c Context) StreamingManager() storetypes.StreamingManager { return c.streamingManager }
func (c Context) CometInfo() comet.BlockInfo                    { return c.cometInfo }
func (c Context) HeaderInfo() header.Info                       { return c.headerInfo }
func (c Context) TxIndex() int                                  { return c.txIndex }
func (c Context) MsgIndex() int                                 { return c.msgIndex }
func (c Context) TxCount() int                                  { return c.txCount }
func (c Context) BlockGasUsed() uint64                          { return c.blockGasUsed }
func (c Context) IncarnationCache() map[string]any              { return c.incarnationCache }
func (c Context) BlockGasWanted() uint64                        { return c.blockGasWanted }

// BlockHeader returns the header by value.
func (c Context) BlockHeader() cmtproto.Header {
	return c.header
}

// HeaderHash returns a copy of the header hash obtained during abci.RequestBeginBlock
func (c Context) HeaderHash() []byte {
	hash := make([]byte, len(c.headerHash))
	copy(hash, c.headerHash)
	return hash
}

func (c Context) ConsensusParams() cmtproto.ConsensusParams {
	return c.consParams
}

func (c Context) Deadline() (deadline time.Time, ok bool) {
	return c.baseCtx.Deadline()
}

func (c Context) Done() <-chan struct{} {
	return c.baseCtx.Done()
}

func (c Context) Err() error {
	return c.baseCtx.Err()
}

func NewContext(ms storetypes.MultiStore, header cmtproto.Header, isCheckTx bool, logger log.Logger) Context {
	// https://github.com/gogo/protobuf/issues/519
	header.Time = header.Time.UTC()
	return Context{
		baseCtx:              context.Background(),
		ms:                   ms,
		header:               header,
		chainID:              header.ChainID,
		checkTx:              isCheckTx,
		sigverifyTx:          true,
		logger:               logger,
		gasMeter:             storetypes.NewInfiniteGasMeter(),
		minGasPrice:          DecCoins{},
		eventManager:         NewEventManager(),
		kvGasConfig:          storetypes.KVGasConfig(),
		transientKVGasConfig: storetypes.TransientGasConfig(),
		txIndex:              -1,
		msgIndex:             -1,
	}
}

// WithContext returns a Context with an updated context.Context.
func (c Context) WithContext(ctx context.Context) Context {
	c.baseCtx = ctx
	return c
}

// WithMultiStore returns a Context with an updated MultiStore.
func (c Context) WithMultiStore(ms storetypes.MultiStore) Context {
	c.ms = ms
	return c
}

// WithBlockHeader returns a Context with an updated CometBFT block header in UTC time.
func (c Context) WithBlockHeader(header cmtproto.Header) Context {
	// https://github.com/gogo/protobuf/issues/519
	header.Time = header.Time.UTC()
	c.header = header
	return c
}

// WithHeaderHash returns a Context with an updated CometBFT block header hash.
func (c Context) WithHeaderHash(hash []byte) Context {
	temp := make([]byte, len(hash))
	copy(temp, hash)

	c.headerHash = temp
	return c
}

// WithBlockTime returns a Context with an updated CometBFT block header time in UTC with no monotonic component.
// Stripping the monotonic component is for time equality.
func (c Context) WithBlockTime(newTime time.Time) Context {
	newHeader := c.BlockHeader()
	// https://github.com/gogo/protobuf/issues/519
	newHeader.Time = newTime.Round(0).UTC()
	return c.WithBlockHeader(newHeader)
}

// WithProposer returns a Context with an updated proposer consensus address.
func (c Context) WithProposer(addr ConsAddress) Context {
	newHeader := c.BlockHeader()
	newHeader.ProposerAddress = addr.Bytes()
	return c.WithBlockHeader(newHeader)
}

// WithBlockHeight returns a Context with an updated block height.
func (c Context) WithBlockHeight(height int64) Context {
	newHeader := c.BlockHeader()
	newHeader.Height = height
	return c.WithBlockHeader(newHeader)
}

// WithChainID returns a Context with an updated chain identifier.
func (c Context) WithChainID(chainID string) Context {
	c.chainID = chainID
	return c
}

// WithTxBytes returns a Context with an updated txBytes.
func (c Context) WithTxBytes(txBytes []byte) Context {
	c.txBytes = txBytes
	return c
}

// WithLogger returns a Context with an updated logger.
func (c Context) WithLogger(logger log.Logger) Context {
	c.logger = logger
	return c
}

// WithVoteInfos returns a Context with an updated consensus VoteInfo.
func (c Context) WithVoteInfos(voteInfo []abci.VoteInfo) Context {
	c.voteInfo = voteInfo
	return c
}

// WithGasMeter returns a Context with an updated transaction GasMeter.
func (c Context) WithGasMeter(meter storetypes.GasMeter) Context {
	c.gasMeter = meter
	return c
}

// WithBlockGasMeter returns a Context with an updated block GasMeter
func (c Context) WithBlockGasMeter(meter storetypes.GasMeter) Context {
	c.blockGasMeter = meter
	return c
}

// WithKVGasConfig returns a Context with an updated gas configuration for
// the KVStore
func (c Context) WithKVGasConfig(gasConfig storetypes.GasConfig) Context {
	c.kvGasConfig = gasConfig
	return c
}

// WithTransientKVGasConfig returns a Context with an updated gas configuration for
// the transient KVStore
func (c Context) WithTransientKVGasConfig(gasConfig storetypes.GasConfig) Context {
	c.transientKVGasConfig = gasConfig
	return c
}

// WithIsCheckTx enables or disables CheckTx value for verifying transactions and returns an updated Context
func (c Context) WithIsCheckTx(isCheckTx bool) Context {
	c.checkTx = isCheckTx
	c.execMode = ExecModeCheck
	return c
}

// WithIsReCheckTx called with true will also set true on checkTx in order to
// enforce the invariant that if recheckTx = true then checkTx = true as well.
func (c Context) WithIsReCheckTx(isRecheckTx bool) Context {
	if isRecheckTx {
		c.checkTx = true
	}
	c.recheckTx = isRecheckTx
	c.execMode = ExecModeReCheck
	return c
}

// WithIsSigverifyTx called with true will sigverify in auth module
func (c Context) WithIsSigverifyTx(isSigverifyTx bool) Context {
	c.sigverifyTx = isSigverifyTx
	return c
}

// WithExecMode returns a Context with an updated ExecMode.
func (c Context) WithExecMode(m ExecMode) Context {
	c.execMode = m
	return c
}

// WithMinGasPrices returns a Context with an updated minimum gas price value
func (c Context) WithMinGasPrices(gasPrices DecCoins) Context {
	c.minGasPrice = gasPrices
	return c
}

// WithConsensusParams returns a Context with an updated consensus params
func (c Context) WithConsensusParams(params cmtproto.ConsensusParams) Context {
	c.consParams = params
	return c
}

// WithEventManager returns a Context with an updated event manager
func (c Context) WithEventManager(em EventManagerI) Context {
	c.eventManager = em
	return c
}

// WithPriority returns a Context with an updated tx priority
func (c Context) WithPriority(p int64) Context {
	c.priority = p
	return c
}

// WithStreamingManager returns a Context with an updated streaming manager
func (c Context) WithStreamingManager(sm storetypes.StreamingManager) Context {
	c.streamingManager = sm
	return c
}

// WithCometInfo returns a Context with an updated comet info
func (c Context) WithCometInfo(cometInfo comet.BlockInfo) Context {
	c.cometInfo = cometInfo
	return c
}

// WithHeaderInfo returns a Context with an updated header info
func (c Context) WithHeaderInfo(headerInfo header.Info) Context {
	// Settime to UTC
	headerInfo.Time = headerInfo.Time.UTC()
	c.headerInfo = headerInfo
	return c
}

func (c Context) WithTxIndex(txIndex int) Context {
	c.txIndex = txIndex
	return c
}

func (c Context) WithTxCount(txCount int) Context {
	c.txCount = txCount
	return c
}

func (c Context) WithMsgIndex(msgIndex int) Context {
	c.msgIndex = msgIndex
	return c
}

func (c Context) WithBlockGasUsed(gasUsed uint64) Context {
	c.blockGasUsed = gasUsed
	return c
}

func (c Context) WithBlockGasWanted(gasWanted uint64) Context {
	c.blockGasWanted = gasWanted
	return c
}

// TODO: remove???

func (c Context) IsZero() bool {
	return c.ms == nil
}

func (c Context) WithValue(key, value any) Context {
	c.baseCtx = context.WithValue(c.baseCtx, key, value)
	return c
}

func (c Context) Value(key any) any {
	if key == SdkContextKey {
		return c
	}

	return c.baseCtx.Value(key)
}

// ----------------------------------------------------------------------------
// Store / Caching
// ----------------------------------------------------------------------------

// KVStore fetches a KVStore from the MultiStore.
func (c Context) KVStore(key storetypes.StoreKey) storetypes.KVStore {
	return gaskv.NewStore(c.ms.GetKVStore(key), c.gasMeter, c.kvGasConfig)
}

// TransientStore fetches a TransientStore from the MultiStore.
func (c Context) TransientStore(key storetypes.StoreKey) storetypes.KVStore {
	return gaskv.NewStore(c.ms.GetKVStore(key), c.gasMeter, c.transientKVGasConfig)
}

// ObjectStore fetches an object store from the MultiStore,
func (c Context) ObjectStore(key storetypes.StoreKey) storetypes.ObjKVStore {
	return gaskv.NewObjStore(c.ms.GetObjKVStore(key), c.gasMeter, c.transientKVGasConfig)
}

// CacheContext returns a new Context with the multi-store cached and a new
// EventManager. The cached context is written to the context when writeCache
// is called. Note, events are automatically emitted on the parent context's
// EventManager when the caller executes the write.
func (c Context) CacheContext() (cc Context, writeCache func()) {
	cms := c.ms.CacheMultiStore()
	cc = c.WithMultiStore(cms).WithEventManager(NewEventManager())

	writeCache = func() {
		c.EventManager().EmitEvents(cc.EventManager().Events())
		cms.Write()
	}

	return cc, writeCache
}

func (c Context) GetIncarnationCache(key string) (any, bool) {
	if c.incarnationCache == nil {
		return nil, false
	}
	val, ok := c.incarnationCache[key]
	return val, ok
}

func (c Context) SetIncarnationCache(key string, value any) {
	if c.incarnationCache == nil {
		// noop if cache is not initialized
		return
	}
	c.incarnationCache[key] = value
}

func (c Context) WithIncarnationCache(cache map[string]any) Context {
	c.incarnationCache = cache
	return c
}

var (
	_ context.Context    = Context{}
	_ storetypes.Context = Context{}
)

// ContextKey defines a type alias for a stdlib Context key.
type ContextKey string

// SdkContextKey is the key in the context.Context which holds the sdk.Context.
const SdkContextKey ContextKey = "sdk-context"

// WrapSDKContext returns a stdlib context.Context with the provided sdk.Context's internal
// context as a value. It is useful for passing an sdk.Context  through methods that take a
// stdlib context.Context parameter such as generated gRPC methods. To get the original
// sdk.Context back, call UnwrapSDKContext.
//
// Deprecated: there is no need to wrap anymore as the Cosmos SDK context implements context.Context.
func WrapSDKContext(ctx Context) context.Context {
	return ctx
}

// UnwrapSDKContext retrieves a Context from a context.Context instance
// attached with WrapSDKContext. It panics if a Context was not properly
// attached
func UnwrapSDKContext(ctx context.Context) Context {
	if sdkCtx, ok := ctx.(Context); ok {
		return sdkCtx
	}
	return ctx.Value(SdkContextKey).(Context)
}
